I am having the same problem as chankster. I tried all of the things in the troubleshooting list on the arduion website, and none of them worked. I tried linux, windows xp (in virtualbox with usb port forwarded), and windows vista x64, and all gave the same error. (avrdude: stk500_getsync(): not in sync: resp=0x00, avrdude: stk500_disable(): protocol error, expect=0x14, resp=0x51). This is a brand new arduino mega. Just came in today from liquidware. The loopback works fine with the serial monitor. I have the correct port and board selected. When I try to send the blink program, the receive led blinks three times, but the transmit light never comes on. Any ideas?
Here's the response I got from the guys at liquidware
Hi Travis,
At first I didn't believe it, because I have my Mega here and I just programmed just fine!
So I told Mike about this and he suggested grabbing a Mega from the latest batch. He tried to program it, but got the same issue you described -it can't program!
There is definitively something different about the Megas produced 1 months ago versus the more recent batches.
I've copied Mike here because he is in regular touch with the Arduino guys in Italy. He's getting in touch them now and as soon as I hear more, I'll keep you posted.
hey guys, i just saw this post come up about the mega... i don't really know what it might be, but the one i have at home works perfectly? i have a vista laptop that pretty much never worked (for some reason the driver crashes my computer every once in a while when it downloads, but that's with the diecimila and duemilanove too), so i always do programming on my xp desktop.
sadly i'm still at work but i'm going to run home as soon as i can to see if i can help. in the meantime i just emailed chris too i think he's home, and maybe he can see what's up?
Hi... i just tested 6 of the new Megas in my book case and none of them will program with Arduino 15 or 16.
i'm going to test the rest and see if i can figure out why these Arduinos aren't working...
update...
I just checked all of the Arduino Megas i have in my apartment...
The 3 that i first bought (in April) from the arduino team in italy worked fine.
The new 58 Arduino Megas (i bought in May) don't work at all... not a single will program!
I tested the ftdi usb circuitry and that checks out fine...
I just took out my AVR ISPMKII and i will test the fuse bits on the processor to see if they are different from my working Megas...
Maybe somebody used a bit too much solder paste on the fat chip. The pin pitch is similar to the FTDI chip though and that has worked before.
Or die DTR capacitor is borked, or the FTDI chip spits out inverted signals or... whatever.
all the arduinos had an incorrect cap placed on them...
so i looked at the reset pulses on both sides of this capacitor to see if it was charging properly when the reset was sent from the ftdi chip...
this was in fact the case...
the ftdi chip was outputing the correct signal, yet the arduino wasn't being reset...
so i replaced it with a 100nF capacitor that i found lying around from the touchshields i built...
the only problem is that the 100nF i used was 0402 surface mount technology... but hey
and...
program!
and fixed
if you bought an Arduino from my website, give me a call on my cell phone (860 930 6480) or shoot me an e-mail ( mike.gionfriddo@gmail.com ) and i will mail you out a fixed MEGA as soon as possible...
Good troubleshooting, thanks for sharing your experiance.
Looking back now that we know the root cause, a test using the manual reset button while uploading a sketch would have worked and helped isolate the problem quicker and with less steps? Sorry, I was a hardware troubleshooter before retirement and can't help myself, I always tried to keep a lessons learned list on equipment I had to support.